Biomedical subjects

J Chodakowska

Publications and source records attributed to J Chodakowska.

97 records · Page 6Linked to original sources

PubMedDate not supplied

Plasma and urinary catecholamines and metabolites during physical exercise in essential hypertension.

The effect of physical exercise on plasma catecholamines and urinary catecholamines and metabolites was studied in 11 patients with established essential hypertension, 5 patients with borderline hypertension, and 9 healthy volunteers. Resting plasma noradrenaline and the changes following exercise were similar in all the investigated groups. Although the resting urinary noradrenaline excretion was similar in patients and in controls, an exaggerated increase of noradrenaline excretion occurred in hypertensive patients during physical work. This finding suggests sympathetic overreactivity in essential hypertension. The increased plasma levels of adrenaline, found in established hypertension, were associated with its diminished urinary clearance. These results imply altered renal handling of adrenaline in essential hypertension. Physical exercise was associated with enhancement of metabolism of noradrenaline to 3-methoxy,4-hydroxy-phenylglycol in all groups of subjects, but the stimulation of this pathway was particularly pronounced in healthy subjects. In essential hypertension, the pattern of urinary excretion of catecholamines and metabolites suggests impaired noradrenaline metabolism during exercise. The only characteristic feature of borderline, as opposed to established hypertension, was the increased urinary excretion of dopamine.

Adult↗

PubMedDate not supplied

Plasma renin activity, aldosterone and cortisol levels during physical exercise in essential hypertension.

Plasma renin activity, aldosterone and cortisol levels, as well as renal blood flow were studied in borderline and established hypertensive patients and in healthy control subjects at rest and following graded dynamic upright exercise. Resting plasma renin activity was elevated in established hypertension, renal blood flow at rest was decreased in patients with borderline hypertension but its per cent decrease during exercise was similar in all groups. Following exercise, plasma renin activity increased in all groups but a step-wise increase with graded exercise occurred only in borderline hypertension. Resting plasma aldosterone and cortisol levels were similar in all groups. In the hypertension patients physical exercise was associated with disproportional changes of plasma renin activity and aldosterone levels. Plasma cortisol displayed patterns which were roughly similar to those or aldosterone in the control group an in established hypertension, but not in the borderline group, where the most pronounced increased of aldosterone level was associated with the lowest level of cortisol. It is concluded that the physiological response of the renin-angiotensin-aldosterone system to physical exercise is altered in essential hypertension.

Adult↗

PubMedDate not supplied

Metabolism of 3H-catecholamines in the brain of spontaneously hypersensitive rats (SHR) after running stress.

The influence of stress on the metabolism of adrenaline (A) and noradrenaline (NA) in the prosencephalon (PC) and rhombencephalon (RC) of SHR and normotensive Wistar rats (WR) was studied. After intraperitoneal injection of 3H-tyrosine, radioactivity of 3H-adrenaline (3H-A), 3H-noradrenaline (3H-NA), total 3H-3-methoxy-4-hydroxyphenylglycol (3H-MHPG), total 3H-3,4-dihydroxyphenylglycol (3H-DHPG) and 3H-vanillylmandelic acid (3H-VMA) was measured in PC and RC of SHR and WR, non-stressed or subjected to running stress. Stress induced a significant decrease of 3H-A level in PC and RC of 8-week-old SHR while no stress-related changes in 3H-NA level were found in either part of the brain of SHR. In RC, 3H-A level was lower in older than in younger non-stressed SHR and decreased further after stress. In all SHR, stress enhanced formation of total 3H-MHPG and/or 3H-DHPG in PC, while increased 3H-VMA level was found only in PC of 24-week-old and in RC of 8-week-old stressed SHR. The results suggest that the decrease of the level of 3H-A in the brain of SHR is involved in their reaction to stress and may depend on increased metabolism mainly to glycols but also to VMA. The lower 3H-NA and 3H-A levels in the prosencephalon of non-stressed young and older SHR, concomitant with unaltered or elevated formation of their metabolites, may suggest higher release of the transmitters involved in the pathogenesis of spontaneous hypertension.

Animals↗

PubMedDate not supplied

Metabolism of 3H-catecholamines in the heart and adrenals of spontaneously hypertensive rats (SHR) after running stress.

The metabolism of 3H-catecholamines after i.p. injection of 3H-tyrosine was studied in the heart and adrenals of spontaneously hypertensive (SHR) and normotensive Wistar (NCR) rats at rest and following running stress. In the heart of 8-week-old NCR a sharp stress-induced increase of the levels of 3H-A and 3H-DA with an elevation of the levels of their metabolites was observed. In contrast, there was no stress-related change in the levels of 3H-NA, 3H-A and 3H-VMA in the hearts of young SHR, while the 3H-DA level, though increased after stress, remained still lower than in the age-matched NCR. In the phase of established hypertension (24 weeks) lower levels of 3H-NA and 3H-A in the heart already present at rest, as compared with NCR, remained lower after stress but the elevation of the level of their metabolites 3H-VMA and 3H-MA, was similar in both strains. In the adrenals of 8-week-old SHR the basal 3H-A level was already higher than in NCR. Stress provoked a marked decrease of adrenal 3H-A accompanied by increased formation of 3H-MA and an increase in the levels of 3H-NA and 3H-DA, more pronounced in SHR than NCR. In the phase of advanced hypertension a further elevation of 3H-A and 3H-MA and an increase of basal 3H-DA level in the adrenals were found at rest. The decreased levels of 3H-catecholamines in the heart of stressed young and non-stressed older SHR may indicate an increase in their rate of release and/or their impaired synthesis. An increased basal level of 3H-A in the adrenals of SHR concomitant with the development of hypertension, may reflect an increased synthesis and/or decreased release, as evidenced by the proportionally lower increase of its extraneuronal metabolite 3H-MA. The adrenal response to stress, more intense in SHR than in NCR, may be considered as due to enhanced release of 3H-A from the gland.

Adrenal Glands↗

PubMedDate not supplied

[Blood pressure in young men with a family history of primary hypertension--traditional and 24-hour blood pressure measurements].

Blood pressure was measured in two groups of young males-group S-55 men with positive family history of essential hypertension (EH) and group K-11 men with negative family history of EH (mean age 24.5 +/- 3.3 and 23.5 +/- 4.7 years). Two methods of blood pressure measurement--traditional blood pressure measurement (method A) and automatic ambulatory indirect blood pressure monitoring (method B) were used. Blood pressure was higher in group S than in group K-method A 140 +/- 14/86 +/- 10 vs 122 +/- 10/73 +/- 8 mm Hg; method B: 132 +/- 11/78 +/- 10 vs 123 +/- 8/72 +/- 7 mm Hg. Contrary to group K, in group S discrepancies in the frequency of diagnosis of systolic or diastolic hypertension were found between the two methods of blood pressure measurement. These results indicate that in young males the traditional method of blood pressure measurement may provide a false positive diagnosis of hypertension, but both methods of blood pressure measurement used in this work were effective in the diagnosis of normotension. As a population the young males with positive family history of EH have higher blood pressure then young males with negative family history of EH.

Adult↗

PubMedDate not supplied

[Isometric exercise and cold pressor test in young men with a family history of essential hypertension].

An exaggerated pressor reaction to the isometric exercise and cold pressor test (CPT) is found to be a predictor or future hypertension. In the two groups of young males: 51 men with positive family history of essential hypertension (EH) (mean age: 24.3 +/- 3.3 years, group S) and 11 men with negative history of EH (mean age: 23.5 +/- 3.7 years, group K) the blood pressure responsiveness to the handgrip test (HG) and CPT were evaluated. Ambulatory systolic (SBP) and diastolic (DBP) blood pressure were higher in S then K (respectively: 136 +/- 11/81 +/- 10 mm Hg vs 126 +/- 4/76 +/- 6 mm Hg, p < 0.05). The elevation of blood pressure after HG (30% of maximal voluntary contraction for 3 min.) was higher in K than S (respectively: delta SBP = 37 +/- 20 vs 21 +/- 17 mm Hg i delta DBP = 27 +/- 20 vs 7 +/- 12 mm Hg, p < 0.05). Similarly, after CPT (by immersing the left hand and forearm in ice-cold water for 2 min.) the elevation of blood pressure was higher in K than S (respectively: delta SBP = 22 +/- 11 vs 12 +/- 12 mm Hg i delta DBP = 17 +/- 12 vs 9 +/- 9 mm Hg, p < 0.05). These results do not confirm an exaggerated blood pressure responsiveness to the HG test or CPT in young males with positive family history of EH, irrespectively to the diagnosis of normotension or borderline hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Pathogenesis of essential hypertension--present views.

The paper reviews the main lines of research pertaining to modern understanding of pathogenesis of essential hypertension. Attention is focused on the role of sympathetic activity, including the neuropeptide Y, as well as on those of atrial natriuretic peptide, endothelins and nitric oxide. The concept of endothelial dysfunction is discussed as a possible factor contributing to the development of hypertension, but also as its sequel. Finally, hyperinsulinemia and insulin resistance are viewed within a scope of interrelated factors of possible pathogenetic significance in essential hypertension. Genetic studies are singled out as the most promising line of further research.

Atrial Natriuretic Factor↗